Modeling Thermoregulatory Responses to Cold Environments

Abstract

The ability to model and simulate the rise and fall of core body temperature is of significant interest to a broad spectrum of organizations. These organizations include the military, as well as both public and private health and medical groups. To effectively use cold models, it is useful to understand the first principles of heat transfer within a given environment as well as have an understanding of the underlying physiology, including the thermoregulatory responses to various conditions and activities. The combination of both rational or first principles and empirical approaches to modeling allow for the development of practical models that can predict and simulate core body temperature changes for a given individual and ultimately provide protection from injury or death. The ability to predict these maximal potentials within complex and extreme environments is difficult. The present work outlines biomedical modeling techniques to simulate and predict coldrelated injuries, and discusses current and legacy models and methods.

Use case for predictive physiological models: tactical insights about frozen Russian soldiers in Ukraine

“…Determining threshold points for the onset of cold-related injuries is complicated due to individual variability in responses to cold and the complexity of conditions in which they occur [ 13 , 36 ]. Additionally, there can be significant variation in the amount of stress that can occur to a given individual [ 37 ].…”

“…From a modelling and simulation perspective, thresholds have been set for loss of dexterity at ~8°C, onset of pain to begin at ~5°C, and frostbite (<1°C) [ 13 , 36 ]. Tables 2 and 3 show the predicted times to reach general skin temperature thresholds both within the vehicle ( Table 2 ) and outside ( Table 3 ).…”

“…Biophysical measures of dry and evaporative resistances are generally required for interpreting and/or calculating a thermal response [ 7 , 8 , 12 , 13 ]. Biophysical properties used for the present modelling are shown in Table 1 , where the uniforms are the same except for different gloves and boots.…”

“…Mathematical models and AI-based computational methods for predicting human thermal responses have been used for mission planning and for preventing cold stress injuries [ 12 , 13 ]. Computational models to account for human physiological and thermoregulatory responses along with data on the biophysical properties of clothing can be used to quantitatively model responses [ 14–19 ].…”